Novel 16beta-alkyl-17-oxygenated steroids and processes



United States Patent 3,461,144 NOVEL IGB-ALKYL-U-OXYGENATED STEROIDS AND PROCESSES David Taub, Metuchen, Norman L. Wendler, Summit, and Harry L. Slates, Madison, N.J., assignors to Merck 8: (10., Inc., Rahway, N.J., a corporation of New Jersey No Drawing. Original application Mar. 19, 1958, Ser. No. 722,300. Divided and this application Mar. 1, 1960, Ser. No. 11,983

Int. Cl. C07c 167/10, 167/26, 169/34 US. Cl. 260-39145 2 Claims This invention is concerned generally with novel steroid compounds and with processes of preparing the same, more particularly, it relates to 16,8-alkyl-l1-0xygenated steroids of the pregnane series unsaturated in ring A. It relates also to novel processes for producing 16,8-alkyl steroids as well as 16a-alkyl steroids.

This application is a division of application Ser. No. 722,390, filed Mar. 19, 1958, and now abandoned.

The new products of our invention may be represented by the following structural formula:

CHaOR' where R is alkyl, R is hydrogen or aeyl, R" is hydroxy or oxygen, and X is hydrogen or halogen. The broken line between carbon atoms 1 and 2 indicates that a double bond may be present in this position.

The 16fi-alkyl steroids produced in accordance with the present invention possess extremely high anti-inflammatory activity, considerably greater than that of the parent steroids, and are especially effective for the treatment of arthritis and related diseases since they can be administered for their cortisone-like action in extremely low dosage thereby minimizing undesired side effects. The activity of 16 beta-alkyl steroids is especially novel as all previous group substitution modifications of cortical steroids which have resulted in increased anti-inflammatory activity have involved introduction of alpha-substituents.

In preparing our novel chemical compounds, the starting material utilized may be a 3-substituted-11-oxygenated-16-pregnene-20-one or 3-substituted-l l-oxygenated- 16-al1opregnene-20-one which may be identified by the following structural formula "ice toxy-16-pregnene-11,20-dione which is represented by the following formula is utilized as the starting material. However, it is clear to those skilled in the art that other starting materials, such as those described above, may be similarly converted to the desired end products.

It has been found that 3a-acetoxy-l6-pregnene-l1,20- dione may be caused to react with diazoalkanes, such as diazomethane and diazoethane to form 3a-acetoxy-16u, 17a-alkyleneazopregnane-l1,20-dione which has the following structural formulawherein R is hydrogen or alkyl.

Upon heating 3a-acetoxy-16a,17a-alkyleneazopregnane- 11,20-dione, there is formed primarily 3a-acetoxy-16- alkyl-l6-pregnene-11,20-dione which may be represented by the following formula- AcO-- wherein R is alkyl as above.

Heating 30: acetoxy 16a,17a-alkyleneazopregnane-l l, 20-dione also results in the formation of a small quantity of each of the two corresponding isomeric forms namely, the cyclopropane, 3-acetoxy-16u,17a-alkylenepregnane-11, 20-dione, which has the following structural formulawherein R'" is hydrogen or alkyl and exocyclic olefin, 3- acetoxy-16-alkylene-pregnane-11,20-dione, which may be represented by the formula where R is hydrogen or alkyl as above.

Treatment of the above isomeric form, namely the 3- acetoxy-16-a1kylenepregnane-11,20-dione with an alkali hydroxide yields 16a-alkyl-3a-hydroxy-16-pregnene-11,20- dione which has the formula wherein R is alkyl.

Oxidation of 3u-acetoxy-16-a1ky1-16-pregnene-11,20- dione, the major isomer obtained above, with an oxidizing agent such as hydrogen peroxide in the presence of sodium hydroxide or peracids such as peroxytrifiuoracetic acid results in the formation of 16p-alky1-16a,17a-epoxy-3 a-hydroxy-pregnane-l1,20-dione which has the structural formula-- wherein R is as above.

Upon treatment of 16p-a1ky1-16a,l7ot-epoxy-3a-hydroxy-pregnane-l1,20-dione with a strong acid such as perchloric acid there is formed an olefin mixture of 16- a1kyl-3u,17u-dihydroxy-15-pregnene-11,20-dione and 16- alkylene-3a,17ot-dihydroxy-pregnane 11,20 dione which may be represented as follows iii): w

and

wherein R' is hydrogen or alkyl and R is as above.

Treatment of the mixture of 16-alky1-3a,17 u-dihydroxy- 15-pregnene-11,20-dione and 16 alkylene 30:,1711 dihydroxypregnane-11,20-dione successively with lithium aluminum hydride and sodium metaperiodate results in a mixture of the endocyclic 16-alkyl-3a,1lfi-dihydroxy-IS- etiocho1ene-17-one and the exocyclic, 16-alkylene-3a,11[3- dihydroxyetiocholane-17-one having the structural forwherein R" is hydrogen or alkyl and R is alkyl as above.

Upon treatment of 16fi-a1kyl- 16u,17a epoxy 3a-hydroxy-pregnane-l1,20-dione with hydrogen bromide in acetic acid there is formed 3a-acetoxy-l6-alkylene-17ahydroxy-pregnane-l1,20-dione, uncontaminated with the IS-pregnene isomer. There is also produced 3ot-acetoxy- 16-alkyl-15-bromo16-pregnene-11,20-dione which may be represented by the following formula- .AcO-

wherein R is alkyl. The 3a-acetoxy-16-alkyl-15-bromo-l6- pregnene-11,20-dione thus produced is an important intermediate in the preparation of other active steroids.

The 3a-acetoxy-16 alkyl 15 bromo 16 pregnene- 11,20 dione may be reacted with pyridine to form 3a-acetoxy-16-alkyl-14, l6-pregnadiene-1 1,20-dione which has the formula wherein R is alkyl and R' is acetyl; the latter compound may be hydrolyzed to the corresponding 3u-ol which has the above formula wherein R is alkyl and R is H.

Hydrogenation of the mixture of 16-alkyl-3a-17a-dihydroxy-lS-pregnene-l1,20-dione and 16-alkylene-3a-17a-dihydroxy-pregnane-l1,20-dione with hydrogen in the presence of a hydrogenation catalyst such as palladium on calcium carbonate results in the formation of a mixture of 16a-alkyl-3u,l7u-dihydroxypregnane-11,20-dione and 16,8-alky1-3a-17a-dihydroxypregnane-11,20 dione which may be represented as follows I ll l Bromination of the above epimeric mixture of 16aalkyl-3u,17u-dihydroxypregnane-11,20 dione and 16;?- alkyl-3u,17ot-dihydroxypregnane-11,20-dione results in the formation of an epimeric mixture of 16a-alkyl-21-bromo- 3a,17a-dihydroxypregnane-11,20-dione and 1618-alky1-2lbromo-3 11,17 a-dihydroxypregnane-l1,20-di0ne which may be represented as follows- CHIBI' (IJH BI l ---orr -CU f C6 wherein R is as above.

The above epimeric mixture of 16a-alkyl-21-bromo- 3a,17a-dihydr0xypregnane-l1,20-dione and 16/3-alky1-21- acid results in the formation of a mixture of 16a-alkyl- 17a,2l-dihydroxypregnane13,11,20-trione ZI-acetate and 16,6-alkyl-17a,2l-dihydroxypregnane-3,1,20 trione 21- acetate which have the following structural formulae- (IJHiOAG CHzOAc --orr and ' wherein R is as above.

bromo 3a,l7a-dihydroxypregnane-l1,20-dione may be reacted with potassium acetate to form an epimeric mixture of 16a-alkyl-3a,17u,2l-trihydroxypregnane-l1,20 dione 21-acetate and 16B-alkyl-3a-17u,21-trihydroxypregnane- 11,20-dione 21-acetate which may be represented by the following formulae- CHQOAO CHzOAC wherein R is as above.

The above epimeric mixture may be separated by chromatography or crystallization at this stage or carried further.

Reaction of a mixture of 16a-alkyl-3a,17a,21-trihydroxy-pregnane-l1,20-dione 21-acetate and 16B-alkyl-3u, 170:,2l-trihydroxypregnane-l1,2l-dione 21-acetate with an oxidizing agent such as N-bromosuccinimide or chromic The mixture of 16a-al-kyl-17oz,2l-dihydroxypregnane- 3,11,20-trione 2l-acetate and l6fl-alkyl-l7a,2l-dihydroxypregnane-3,11,20-trione 2-acetate can be separated by chromatographic procedures.

The 16;.8-alky1-17a,21-dihydroxypregnane-3,11,20 trione 21-acetate is reacted with bromine to form l6fi-alkyl- 4-bromo-170:,2l-dihydroxypregnane3,11,20 trione 21- acetate which has the following structural formula- CllHaOAc wherein R is alkyl.

The alkyl 4 bromo-17a;l-dihydroxypregnane- 3,11,20-trione 21-acetate obtained above is then reacted with a slurry of semicarbazide hydrochloride and sodium bicarbonate to form the 3-semicarbazone of l6B-alkyl- 17a,2l-dihydroxy-4-pregnene 3,11,20 trione ZI-acetate which may be represented by the following structural formula- CHzO Ac 0 W n mncorvnrrlb wherein R is as above.

The above 3-semicarbazone of 16B-alky1-17a,21-dihydroxy-4-pregnene-3,l1,20-trione 21-acetate is then reacted with, for example, pyruvic acid, in aqueous acetic acid to form 16,6-a1-kyl ;,21 dihydroxy-4-pregnene-3,l1, 20-trione 21-acetate having the following structural formula-- wherein R is as above.

Hz 0 H C=NNHCONH2 NHzCONHN- wherein R is alkyl as above.

Reduction of the 3,20-disemicarbazone of l6fl-alkyl- 17a,2l-dihydroxy-4-pregnene 3,11,20-trione with sodium boronhydride produces the 3,20-disemicarbazone of 16palkyl 11,B,17a,21 trihydroxy 4 pregnene-3,20-dione, which has the following formula:

CHiOH C=NNHCONH2 wherein R is as above.

The 3,20-disemicarbazone of 16}8-alkyl-11,B,17a,21-trihydroxy-4-pregnene-3,20-dione is reacted with pyruvic acid in aqueous acetic acid to remove the semicarbazone groups at the 3 and 20-positions to form 16/8-alkyl-l1fi, 17a,21-trihydroxy-4-pregnene-3,20-dione which may be chemically represented as follows:

CHaOH HO R wherein R is as above. The above compound which may be called 16,8-alkyl hydrocortisone has been found to exhibit marked and effective activity in the treatment of arthritis. 7

Acetylation of 16/3-alkyl-11/3,17a,21-trihydroxy-4-pregnene-30,20-dione at the 21-position is accomplished by reacting this latter compound with acetic anhydride in the presence of pyridine to form 16fl-alkyl-11p,17a,21-trihydroXy-4-pre'gnene-3,20-dione 21-acetate which may be represented as follows:

wherein R is as above.

Other 21-acylates may be prepared by reacting the 2l-alcohol with the appropriate acyl anhydrides.

By reacting 16fl-alkyl-l113,170;,21-trihydroxy-4-pregnene-3,20-dione 21-acetate with methanesulfonyl chloride in dimethylformamide there is formed 16B-a1kyl-l7a,2ldihydroXy-4-,9(11)-pregnadiene-3,204iione 21-acetate of the following structural formula wherein R is as above.

Reacting the latter compound with N-bromo-succinimide forms l6B-alkyl-9u-bromod1fl,17a,21-trihydroxy-4- pregnene-3,20-dione 21-acetate represented by the formula CHzOAc wherein R is as above.

Reacting the latter compound with sodium methoxide producess 16/3 alkyl-9&1lfi-epoxy-l7a,21-dihydroxy-4- pregnene-3,20-dione having the formulawherein R is as above.

The latter compound is acetylated with acetic anhydride in pyridine and then allowed to react with hydrogen fluoride, to form 16p-alkyl-9a-fluoro-11p,l7a,21-trihy- 9 droxy-4-pregnene-3,20-dione 21-acetate of the following structural formula:

pmoac o o --o:Et

Hoft TR wherein R is as above. The 21-acetate can be readily converted to the corresponding 21-01, namely, l6,8-alky1-9ofluoro-l1B,17 x,21-trihydroxy-4-pregnene-3,20 5 dione by hydrolysis. This latter compound may also be called 168- alkyl-9a-fluoro-hydrocortisone and it has been found that this compound is very effective in the treatment of arthritis.

In accordance with this invention, l6fi-alkyl-l7a,21-dihydroxy-ll-oxygenated-1,4-pregnadiene-3,20 dione and 16B alkyl 9oz -fluoro-17u,21-dihydroxy-1l-oxygenated- 1,4-pregnadiene-3,20-dione and the corresponding 21- acylates can be prepared by reacting respectively 165- alkyl 17u,21 dihydroxy 11-oxygenated-pregnane-3,20- dione 21-acetate and 16 3-fllkYl-9oc-flll0l0-17a,21-dil1ydr0xy-11-oxygenated pregnane-3,20-dione 21-acetate with bromine to form the corresponding 16fl-alkyl-2,4- dibromo 170;,21 dihydroxy ll-oxygenated-pregnane- 3,20-dione 21-acetate which has the following structural formula:

wherein R, R" and X are as above, The species represented by the above formula are highly potent antiinflammatory agents.

The 21-acetate esters of these compounds can 'be hydrolyzed to the corresponding alcohols, 16/3-alkyl-17u,21 dihydroxy-l l-oxygenated-1,4-pregnadiene-3,20-dione and 16,6 alkyl 9a fluoro-17ot,21-dihydroxy-ll-oxygenated- 1,4-pregnadiene-3,20-dione represented by the following structural formula CHzOH wherein R and R" are as above.

Alternatively, the 1,4-pregnadiene compounds described above may be prepared from the corresponding 4- pregnene-3-ones by dehydrogenation chemically with selenium dioxide or microbially by means of Bacillus sphaericus.

The following experimental part illustrates in detail some of the compounds which constitute this invention and methods for their production. However, this invention is not to be construed as limited thereby in spirit or in scope since it will be apparent to those skilled in the art that many modifications in materials and methods may be made without departing from the invention.

Example 1.-Preparation of 3cc-aC6tOXy16oc,17oL- methy leneazo-pregnane-1 1,20-dione In a 500-ml. 3-neck flask equipped with condenser, dropping funnel and nitrogen inlet were placed 20 g. of potassium hydroxide in ml. of water, ml. of methanol and 100 m1. of ether. A solution of 10 g. of N-methyl-N-nitrosotosylamide in 50 ml. of ether was placed in the dropping funnel.

Diazomethane was generated by warming the generation flask to 40-45 C. and cautiously adding the N-methyl-N-nitrosotosylamide-ether from the dropping funnel. Nitrogen was utilized to sweep the diazomethane into a solution of 20 g. of 3u-acetoxy-16-pregnene-11,20- dione in 100 ml. of tetrahydrofuran and ml. ether. The process was continued until the steroid solution remained yellow for several hours. The product, 3ozacetoxy l6oc,l7ot methyleneazo-pregnane 11,20 dione largely precipitated from the reaction mixture. After 16 hours, the mixture was filtered, washed with ether and dried in air. Yield 14.24 g., M.P. 186-190 C. (dec.) 2nd crop (on concentration) 4.45 g., M.P. -187 C., 3rd crop, 1.32 g., M.P. 190 C. Total usable material 20.01 g. (90%).

LR. Agg e max.

Analysis.Calculated for C H O N :C, 69.55; H, 8.27. Found: C, 69.37; H. 8.01.

Example 2.Preparation of 3a acetoxy 16 methyl-l6- pregnene 11,20 dione; 3a-acetoxy 16,17a methylenepregnane 11,20 dione; 3a-acetoxy 16 methylenepregnane-11,20-dione and 3a-hydroxy-16-methyl-16- pregnene-l l,20-dione and was taken up in about 150 ml. of acetone, filtered through diatomaceous earth, concentrated to about 100 ml. and ether slowly added to the boiling solution until crystallization occurred. These crystals of 3a-acetoxy-16- methyl-16-pregnene-11,20-dione weighed 19.0 g., M.P. 165-168 C.;

CHQOH max.

2nd crop 5.3 g., M.P. l60-164 C.,

xoHaOH 249, E% 211 max.

3rd crop 5.0 g., M.P. 142-153 C.,

ACHSOH 249, 19% 156 Example 3.Preparation of 1601,17 a-epoxy-3u-hydroxy- 16fi-methylpregnane-11,20-dione A solution of 20.0 g. of 3a-acetoxy-16-methyl-16-pregnene-11,20-dione dissolved in 600 ml. of methanol, was cooled to 18 C., and 80 ml. of 30% hydrogen peroxide followed by 80 ml. of 2.5 N sodium hydroxide were added. Considerable material precipitated from solution, but all redissolved on stirring the reaction mixture at 25 30 C. for 40 minutes. The solution was kept at 20 C. for 18 hours at which time the ultra-violet maximum at 249 had completely disappeared. Then 600 ml. of saturated salt water was slowly added, the crystalline precipitate was filtered, washed with water, and dried in air and in vacuum. The 16a,17a-epoxy-3u-hydroxy-16,6- methylpregnane-l1,20-dione thus formed weighed 17.36 g. (93%); M.P. 176-l77 C., hexagonal prisms M.P. 178- 180 C. from acetone-ether.

max.

Analysis.-Calculated for C H O C, 73.30; H, 8.95. Found: C, 73.23; H, 9.12.

Room temperature acetylation gave the 3a-acetoxy-16u, 17a-epoxy-16fl-methylpregnane-11,20-dione having a melting point of 162164 C.

Analysis.Calculated for C H O C, 71.65; H, 8.51. Found: C, 71.65; H, 8.25.

Example 4.Preparation of an olefin mixture of 351,1712- dihydroxy 16 methyl-IS-pregnene-l1,20-dione and 30a, 17u-dihydroxy-16-methylenepregnane-l 1,20-dione To a solution of 2.69 g. of 16oz,l7a-BPOXY-3oc-l1YdI'OXY- 16,8-methyl-pregnane-l1,20-dione in 55 ml. dioxane was added 27 ml. of 2 M aqueous perehloric acid. The clear solution was kept at -3 C. for 65 hours. Cold water (175 ml.) was added, the slurry chilled to 8 C. and filtered after 30 minutes. The precipitate, containing a mixture of 301,170: dihydroxy 16 methyl-lS-pregnene- 11,20-dione and 3a,17u-dihydroxy-16-methylene-pregnane was washed with water, and dried in air and finally at 50 C. in vacuum. Yield: 2.27 g. (94.5%), M.P. sintering at about 150 C. melting at 158-167 C. The relative proportion of 3a,17a-dihydroxy 16 methyl-15-pregr1ene-11, 20-dione and 3a,Hot-dihydroxy-l6-methylenepregnane-11, 20-dione is estimated to be of the order of 1:1.

1 2 Example 5.-Preparation of 3 01,1 1 B-dihydroXy-16-methyl- 15-etiocholene-17-one and 301,1lfi-dihydroxy-16-methylenetiocholene-17-one Treatment of the mixture of 3a,17a-dihydroxy-16- methyl-15-pregnene-11,20-dione and 3a,17a-dihydroxy-16- methylenepregnane-l1,20-dione successively with lithium aluminum hydride and sodium periodate gave a crystalline mixture (M.P. 166-171 C.) of endocyclic 3a,11fidihydroxy-16-methyl-15-etiocholene-17-one and exocyclic 300,11fi dihydroxy-l6-methylene etiocholane-17-one C-17 ketones with ACHaOH 232.5, E% 200; x0110];

IHHX. max.

The conjugate C=O peaks at 5.80 and 5.87 were of equal intensity indicating the proportions to be 1:1.

Pure 311,115 dihydroxy-16-methylene etiocholane-17- one was prepared similarly from pure 3a-acetoxy-16-methylene-17u-hydroxy-pregnane-11,20-dione obtained by hydrogen bromide opering of the oxide, 3a-acetoxy-16u,17aepoxy-16,8-methyl-pregnane-11,20-dione (see Example 6).

max

Example 6.Preparation of 3u-acetoxy-l7a-hydroxy-16- methylene-pregnane 11,20 dione and 3a acetoxy-lS- bromo-16-methyl-l6-pregnene-11,20-dione max.

Analysis.Calculated for: C H O Br: C, 61.93; H, 7.14; Br, 17.17. Found: C, 61.83; H, 6.99; Br, 16.89.

From the 50:50 petroleum ether-benzene to benzene eluates there was obtained 1.60 g. 3oc-2Cfit0Xy-l7ahydroxy-l6-methylene-pregnane-11,20-dione; prisms from acetone-ether M.P. 198-200 C.

gago az 0:1.00 Aggy 2.95, 5.75, 5.82, 5.87,

Analysis.Calculated for: C H O C, 71.61; H, 8.51. Found: C, 71.51; H, 8.07.

Example 7.Preparation of 30c-21CG1OXY-16-II161111Yl-14,16- pregnadiene-l 1,20-dione 42 mg. of 3a-acetoxy-15-bromo-16-methy1-16-pregnene- 11,20-dione was dissolved in 2 ml. of pyridine. After 18 hours at 25 C. the mixture was concentrated to dryness in vacuo. The solid residue of 3a-acetoxy-16-methyl-14, 16-pregnadiene-11,20-dione was crystallized from ether;

prismatic needles M.P. 185 C.;

xfiEgP 304 m... E: 11,000

Example 8 A solution of 3.05 g. (8.47 millimol) of the olefin mixture of 30:,1711 dihydroxy 16-methyl-15-pregnene-11,20- dione and 3a,17a-dihydroxy-16-methylene-pregnane-11, 20-dione in 80 ml. of methanol was reduced in hydrogen at 1 atmosphere and 25 C. in the presence of 2.0 g. of 25% palladium-calcium carbonate catalyst. Modification of the hydrogenation conditions, pH, solvent, catalyst, etc. alters the isomer ratio significantly. Uptake of the calculated amount of hydrogen was complete in 45 minutes. The mixture was stirred an additional 30 minutes and filtered through diatomaceous earth. The colorless filtrate was taken to dryness and crystallized from ether: a mixture of 3a,l7a-dihydroxy-16a-methylpregnane-11,20-dione and 3a,17u-dihydroxy-16 3-methylpregnane 11,20 dione was obtained and weighed 3.05 g., sintering at 150 C. melting at 166182 C.

iggg 2.79, 2.95, 5.87;

The product consists of 3a,l7u-dihydroxy-l6a-methylpregnane-l1,20-dione and 3a,Not-dihydroxy-16,8-methylpregnane-1l,20-dione in the ratio ca. 7:3 as determined by the amounts of end product isolated below.

Example 9.Alternate preparation of 3a,l7a-dihydroxy- 16u-methylpregnane-11,20-dione and 3a,l7a-dihydIOXylofi-methylpregnane-l1,20-dione A solution of 10.0 g. of 16a,l7a-epoxy-3a-hydroxy- 16B-methylpregnane-l1,20-dione in 180 ml. of dioxane and 112 ml. of 2 M aqeous perchloric acid was prepared. The solution was hydrogenated at 25 C. and 1 atmosphere pressure in the presence of 4.4 g. of 5% palladium on charcoal catalyst. Uptake of one mole of hydrogen was complete in hours. The catalyst was removed by filtration and 300 ml. of 70% saturated sodium chloride was added to the filtrate. After being kept at 0 C. for 30 minutes, the precipitated mixture of 3a,l7a-dihydroxy- 16a-methy1pregnane-11,20-dione and 3a,17a-dihydroxy- 16/3-methylpregnane-11,20-dione was filtered, washed with water and dried in air. Yield: 9.26 g. Solubility analysis in benzene indicated the product to be 75% 3oc,17ot-dihydroxy-lout-methylpregnane-l1,20-dione and 25% 3a, 17x-dihydroxy- 16,8-methylpregnane-1 1,20-dione.

Example lOrSeparation of 30:,170: dihydroxy 16ozmethylpregnane-l1,20-dione and 3u,17a-dihydroxy-16,8- methylpregnane-l 1,20-dione Analysis.Calculated for C H O C, 72.89; H, 9.45. Found: C, 72.97; H. 9.25.

The 16u-methyl and 16fi-methylpregnanes respectively, had R values of 0.55 and 0.35 when chromatographed on Whatman #1 filter paper in the benzene-formamide system.

As described hereinafter, 30,17m dihydroxy 16/3- methylpregnane-l1,20-dione was brominated at position 21 in exactly the same way as the mixture of 16a and 16fl-methyl compounds to give 21-bromo-3a,17a-dihydroxy-16,8-methylpregnane-11,20-dione. This latter compound was similarly converted to 3oc-17oz,21-[1'ihy droxy-16/3-methylpregnane-11,20-dione 21-acetate. This compound was then similarly oxidized at position 3 to give 17a,21 dihydroxy 16,8-methyl 3,11,20 trione 21- acetate.

Example 11.Preparation of a mixture of 3a-acetoxy- 17a-hydroxy-l6u-methyl-pregnane-l1,20-dione and 3aacetoxy-17ot-hydroxy-l6B-methylpregnane-1 1,20-dione To a mixture of 3a,17a-dihydr0xy-l 6tx-methylpregnane- 11,20-dione and 3a,17a-dihydroxy-16,8-methylpregnane- 11,20-di'one dissolved in pyridine was added acetic anhydride at 20 C. A mixture of 3a-acetoxy-l7a-hydroxyl6oc-methylpregnane-l1,20-dione and 3u-acetoxy-17u-hydroxy-lGfi-methylpregnane-1l,20dione separated from solution and was recovered. These prisms sintered at 170 C. and melted at 175 l79 C.

Example 12.Preparation of a mixture of 21-bromo-3u,

l7a-dihydroxy-16a-methylpregnane-1 1,20-dione and 2.1- bromo-3u,17a-dihydroxy-lfi-methylpregnane 11,20- dione A solution of 3.50 g. (9.7 millirnal) of a mixture of 3a,17a-dihydroxy-1oa-methylpregnane-l1,20 dione and 3a,17u-dihydroxy-16/3-methy1pregnane-l1,20 dione obtained as above in 40 ml. of chloroform was warmed to 4045 C. A solution of 1.76 g. (11 millimol) of bromine in 25 ml. of chloroform was added dropwise to the stirred solution such that the color was not darker than pale yellow (ca. 2 drops/see, total time-1 hour). The nearly colorless solution was cooled to 20 C. and 200 ml. of ether was added. The mixture was extracted with excess cold 5% potassium bicarbonate solution, sodium bisulfite solution, and water and dried over magnesium sulfate. The colorless residue after removal of solvent, a mixture of 2l-bromo-3a,17oc-dihydroxy-l6a-methylpregnane-11,20-dione and 21-bromo-3u,Not-dihydroxy- 16fl-methylpregnane-l1,20-dione (4.30 g.) gave a positive tetrazolium test. Paper chromatography (benzene-formamide) resolved the material into 2 spots.

Example 13.Preparation of a mixture of 3a,17u-21- tIlhYdlOXY-IGu-mlhylpI'GgHQllfi-l1,20-(110116 21-acetate and 3a,17a,21-trihydroxy-16fi-methylpregnane 11,20- dione 21-acetate To 4.30 g. of 2l-bromo-3a,l7a-dihydroxy-l6a-methylpregnane-11,20-dione and 21-bromo-3a,17a-dihydroxy- 16,8-methylpregnane-l1,20-dione in ml. of acetone and 0.10 ml. of acetic acid were added 4.83 g. of anhydrous potassium acetate and 3.85 g. of potassium iodide. The stirred mixture was refluxed for 18 hours and concentrated on the water pump to a small volume. Water was added, the product extracted into ethyl acetate, and the organic extract dried over magnesium sulfate. The product (4.25 g.) was a colorless foam that partly crystallized from acetone-ether to give ca. 30% dense cubes sintering at about 150 C., and melting at ZOO-213 C., which paper chromatography showed was mainly 3u,l7a, 21-trihydroxy-16fl-methylpregnane-l 1,20-dione 21-acetate contaminated with some 3a,17a,21-trihydroxy-16a-methylpregnane-1l,20-dione 21-acetate. The LR. spectrum of this material was similar to that of authentic 30L,17ct,21-1Ilhydroxy-l6a-methylpregnane-11,20-dion 2 l-acetate in the functional group region but differed significantly in the fingerprint region. Seeding the mother liquors with authentic. 3a,17o,21-trihydroxy 164x methylpregnane 11,20- dione 21-acetate induced crystallization of crude 30;,1701, 2l-trihydroxy-16a-methylpregnane-11,20-dione 2l-acetate which was purified by repeated crystallization from acetone-ether and shown to be identical with an authentic sample by mixed M.P., LR. and paper chromatographic comparisons.

Example 14.-Preparation of 17a,21-dihydroxy-16a-methylpregnane-3,11,20-trione 21-acetate and 17u,21-dihydroxy-16,8-methylpregnane-3,11,20-trione 21-acetate To the mixture obtained as above of 3a,17oc,21-1IihydI'OXY-16oc methylpregnane-l1,20-dione 21-acetate and 3a, 17oz,21-trihydroxy-16,8-methylpregnane-11,20 dione 21- acetate, 4.0 g., in ml. t-butanol and 20 ml. of water cooled to 10-l5 C., was added 3.5 g. N-bromo-succinimide. The suspension was stirred at 15 C. until all the N- bromosuccinimide had dissolved (90 minutes). The reac tion mixture was kept at 2 C. for about sixteen hours and at 25 C. for 2 hours. Sodium sulfite solution was added to destroy bromine and the mixture concentrated on the water pump to a low volume. A granular precipitate had formed; water was added, the precipitate filtered and washed with Water: 3.30 g., sintering at about 170 C. melting at about 2022l2 C. Extraction of the filtrate with ethyl acetate gave .350 g., M.P. 130 170 C. Since both samples were mixtures by paper chromatography, they were recombined for alumina chromatography. Trituration with 100 ml. hot benzene gave 540 mg. of material M.P. 225 235 C. Chromatography of the remainder on neutral alumina (85 g., 100 ml. fractions) gave 1.324 g. of 17 z,21-dihydroxy-16a-methylpregnane-3, 11,20-trione 21-acetate, M.P. 230 C. from fractions 5-15; (5% CHCl 70% C H Fraction 17-21 (50% CHCl 50% C H to 100% CHCl contained 0.850 g. 17a,21- dihydroxy-16fi-methylpregnane 3,11,20-trione 21-acetate, M.P. 210-213" C. The yield was about 2.0 g. [1.87 g.+ca. .10-.20 g. in mixed fraction 16]. The ratio of l7oc,21-(lihydroxy-l6u-methylpregnane-3,l1,20-trione 2l-acetate to 17oz,21-dihydroxy-16fl-methylpregnane-3,11,20 trione 21- acetate, 2.0: 0.85:7:3, is probably close to the ratio of 3a,17a-dihydroxy-l6a-methylpregnane-l1,20 dione produced in the hydrogenation.

Pure 1712,21 dihydroxy-16B methylpregnane 3,11,20- trione 21-acetate had the following properties:

M.P. 210-212 0. r 2.92, 5.76, 5.81, 5.87

max.

Analysis.Calculated for C H O C, 68.88; H, 8.19. Found: C, 68.81; H, 7.91.

Example 15.Preparation of 4-bromo-17u,21-dihydroxy- 16,8-methylpregnane 3,11,20-trione 21-acetate To a stirred solution of 585 mg. of Null-dihydroxy- 165 methylpregnane 3,11,20 trione 2l-acetate in 10 ml. of acetic acid and 8 ml. of chloroform kept at -l0 C. was added slowly 230 mg. of bromine in 6 ml. of chloroform. After addition was complete, 1.2 g. of sodium acetate in 7 ml. of cold water was added. Additional water was added and the mixture was extracted with chloroform. The chloroform extract was Washed with dilute potassium bicarbonate, water and dried over sodium sulfate. The residue was triturated with ether to give 480 mg. of crystalline 4-brorno-17u,21-dihydroxy 1613 methylpregnane-3,11,20-trione 21-acetate M.P. 165l70 C. dec.

Analysis.Calculated for: C H O Br: Br, 16.08. Found: Br, 15.58.

A second crop of 133 mg. of 4-bromo-17a,21-dihydroxy- 16B methylpregnane 3,11,20 trione 21-acetate was also obtained.

Example 16.Preparation of the 3-semicarbazone of 17d,21 dihydroxy 16B methyl-4-pregnene-3,11,20- trione 21-acetate To 583 mg. of 4-bromo-17a,21-dihydroxy-16B-methylpregnane-3,11,20 trione 21 acetate in 20 ml. of acetonitrile under nitrogen was added a slurry of 600 mg. of semicarbazide hydrochloride and 410 mg. sodium bicarbonate in 4 ml. of water. After 2 hours, the acetonitrile was removed in vacuo, water added and 540 mg. of crystalline 3-semicarbazone of 1754,21-dihydroxy-16fi-methyl- 4-pregnene 3,11,20 trione 21-acetate filtered, Washed with water and dried.

Example 17.Preparation of 1712,21 dihydroxy-16,8- methyl-4-pregnene-3,'l1,20-trione 21-acetate 540 mg. of the semicarbazone of 17a,21-dihydroxy-16fimethyl-4-pregnene 3,11,20-trione 21-acetate was dissolved in 20 m1. of acetic acid, 1.5 ml. of pyruvic acid and 5 ml. of water. After 18 hours at 25 C., water was added and the mixture extracted with chloroform. The chloroform extract was washed with aqueous potassium bicarbonate, water and dried over sodium sulfate. Removal of solvent gave crude l7oc,2l-dihydroxy-16,B methyl 4 pregnene- 3,11,20-trione 21-acetate which was purified by chromatography on neutral alumina and crystallization from acetone-ether (hexagonal plates). The pure material had M.P. 226232 C.,

@3 238 m E=15,600; r359 2.852.98, 5.73, 5.79,

Analysis.--Calculated for C H O C, 69.21; H, 7.75. Found: C, 69.24; H, 7.58.

Example 18.-Preparation of the 3,20-disemicarbazone of 17a,21-dihydroxy-16,B methyl-4-pregnene 3,11,20-trione 21-acetate To a stirred solution of 500 mg. of 17a,21-dihydroxy- 16,8-methyl-4-pregnene 3,11,20-trione 21-acetate (prepared as described in Example 17) in 12.5 ml. of methanol and 3 ml. of dimethylformamide kept under nitrogen was added a slurry of 680 mg. of semicarbazide hydrochloride and 370 mg. of sodium bicarbonate in 1 ml. of water. The stirred mixture was refluxed 3 /2 hours and maintained at 45 C. for 17 hours. It was then cooled to 20 C. and 50 ml. of 50% saturated aqueous sodium chloride was added. After 2 hours at 0 C. the precipitate 0f the 3,20-disemicarbazidone of 17a,2l-dihydroxy-16fi-methyl-4-pregnene- 3,11,20-trione 21-acetate was filtered, washed with water until free of chloride ion and dried in air. Yield over Example l9.-Preparation of the 3,20-disemicarbaz0ne of l1fi,17uc,2l trihydroxy-16,8-methyl-4-pregnene-3,20- dione To a stirred solution of 600 mg. of the 3,20-discmicarbazone of 17a,21-dihydroxy-16,8-methyl-4-pregnene-3, 11,20-trione 21-acetate in 30 ml. of tetrahydrofuran and 11 ml. of water under nitrogen was added 200 mg. powdered sodium borohydride. The stirred suspension was refluxed 45 minutes and then cooled to 15 C. Aqueous acetic acid (3 ml. of 30%) was added cautiously and most of the tetrahydrofuran was removed in vacuum. Addition of 5 ml. of methanol and 5 ml. of water induced the product to crystallize. Following addition of 10 ml. of a saturated sodium chloride solution and aging at 0 C. the product 3,20-disemicarbazone of 1119,1711, 21 trihydroxy 16B methyl-4-pregnene-3,20-dione was filtered, washed with water, and dried in air.

Example 20.Preparation of 11,8,17a,21-trihydroxy-16B- methyl-4-pregnene-3,20-dione To a solution of 510 mg. of reduced 3,20-disemicarbazone of 11,8,17a,21-trihydroxy-16fl-methyl-4-pregnene- 3,20-dione in 5 m1. of acetic acid was added 1.20 ml. of water and 0.50 ml. of pyruvic acid. The solution was kept at 25 C. for eighteen hours. Water (20 ml.) was added, and the mixture was extracted thoroughly with chloroform. The chloroform extract was dried over magnesium sulfate and taken to dryness. The residue was crystallized from acetone-ether to give pure 11fl,17a,21-trihydroxy- 16,8-methyl-4-pregnene-3,20-dione.

Example 21.Preparation of l1,8,17a,21-trihydroxy-l6fimethyl-4-pregnene-3,20-dione 21-acetate The product of the previous Example 20 was acetylated at C. -21 as follows: A solution of mg. of 115,17a, 21-trihydroxy-165-methyl-4-pregnene 3,20 dione in 100 ml. of pyridine and 0.5 ml. of acetic anhydride was prepared. After 18 hours at 25 C., the solution was taken to dryness in vacuo and the solid residue purified by crystallization in acetone-ether to give 11fi,17x,21-trihydroxy-16B-methyl-4-pregnene-3,20-dione 21-acetate.

Example 22.Preparation of 17a,21 dihydroxy 16B- methyl-4,9(1l)-pregnadiene-3,20-dione 21-acetate A solution of 400 mg. of 1lfl,170:,2l-tflhYdfOXY-l6/3- methyl-4-pregnene-3,20-dione 21-acetate in 2.0 ml. dimethyl formamide, 0.8 ml. of pyridine and 0.4 ml. of methanesulfonyl chloride was kept at 75 C. for one hour. The mixture was cooled, water added, and the precipitate filtered, washedwith water and dried in air. The desired 17 :,21 dihydroxy 16,8 methyl 4,9(11)- pregnadiene-3,20-dione 21-acetate was purified by chro matography on alumina (20 g.) and elution of the column with benzene. Crystallization of material eluted by benzene gave pure 17a,2l-dihydroxy-16fl-methyl-4,9(11)- pregnadiene-3,20-dione 21-acetate.

Example 23.Preparation of 9ot-bromo-l1B,l7a,21-trihydroxy-l6fl-methyl-4-pregnene-3,20-dione 2-1-acetate To a mixture of 620 mg. of 17a,2l-dihydroxy-16B- methyl-4,9(11)-pregnadiene 3,20 dione 21-acetate and 330 mg. of N-bromosuccinimide in 10 ml. of dioxane and 3.2 ml. of water cooled to 10 C. Was added 1.8. m1. of cold 1 M aqueous perchloric acid. The mixture was stirred at 15 C. for 3 hours. Excess N-bromosuccinimide was destroyed by addition of aqueous sodium thiosulfate and most of the dioxane was removed in vacuo. About 30 ml. of water was added and crystalline bromohydrin, 9ot-bromo-11B,17a,21-trihydroxy-16 3 methyl 4 pregnene-3,20-dione 21-acetate, was filtered, washed with water, and dried in air.

Example 24.-Preparation' of 95,11;9-epoxy-17u,21-dihydroxy-l6,6-methyl-4-pregnene-3,20-dione 21-acetate To a stirred solution of 100 mg. of the 9ot-bromo-11fi, 17u,2l-trihydroxy-16fl-methyl-4-pregnene-3,20 dione 21- acetate in 3 ml. of tetrahydrofuran and 1 ml. of methanol under nitrogen was added 1.02 ml. of 0.215 N methanolic sodium methoxide. After 10 minutes at 25 C. 0.2 ml. of acetic acid was added and the methanol removed in vacuo. The residue was acetylated with 1.00 ml. of pyridine and 0.5 ml. of acetic anhydride at 60 C. for 70 minutes. The mixture was taken to dryness in vacuo, water added, and the product extracted into chloroform. The residue was crystallized from ether-acetone to give pure 9,8,11 epoxy-17a,21-dihydroxy-16,8-methyl-4-pregnene-3,20-dione 21-acetate.

Example 25.Preparati0n of 9ot-flu0ro-11 8,17a,21-trihydroxy-16B-methyl-4-pregnene-3,20-dione 21-acetate To a solution of 200 mg. of 9 3,l1/3-epoxy-17a,21-dihydroxy-l6fl-methyl-4-pregnene-3,20-dione 21-acetate in 2 ml. of chloroform and 2 ml. of tetrahydrofuran in a polyethylene bottle at 60 C. was added 2 ml. of a 2:1 (by weight) mixture of anhydrous hydrogen fluoride and tetrahydrofuran. After 4 hours at -10 C. the mixture was cooled to 60 C. and cautiously added to a stirred mixture of 30 ml. of 25% aqueous potassium carbonate and 25 m1. of chloroform kept at C. The aqueous phase was further extracted with chloroform and the latter phase washed with water and dried over magnesium sulfate. The residue on crystallization from acetone-ether gave pure 9a-fluoro 11fl,17oc,21 trihydroxy- 16,6-methyl-4-pregnene-3,20-dione 21-acetate.

Example 26.Preparation of 9u-fiLlOIO-11B,17oz,21-t1ihydroxy-16fi-methy1-4-pregnene-3,ZO-dione To a stirred solution of 110 mg. of 9a-f1uoro-11 8,17a, 21 trihydroxy- 1 6fl-methy1-4-pregnene-3,20-dione 21-acetate in 5 ml. of methanol under nitrogen at 25 C. was added 1.00 ml. of 0.26 M methanolic sodium methoxide. After 15 minutes 0.2 ml. of acetic acid in 1 ml. of water was added and the mixture concentrated nearly to dryness. The residue was taken up in ethyl acetate and the ethyl acetate solution was washed with water, dried over magnesium sulfate, and concentrated to dryness. Crystallization of the residue from ethyl acetate gave pure 9afluoro 11fl,17a,21 trihydroxy-l6B-methyl-4-pregnene- 3,20-dione.

Example 27.Preparation of 9a-chloro-11B,17u,21-trihydroxy-16,3-methyl-4-pregnene-3,20-dione 21-acetate To a solution of 100 mg. of 9p,11p-epoxy-17a,21-dihydroxy 16B-methyl 4-pregnene 3,20-dione 21-acetate in 4 ml. of chloroform was added 5 ml. of concentrated hydrochloric acid. The two-phase mixture was stirred .at 25 C. for 1 hour. Addition of water and chloroform extraction gave a crude crystalline product which is partly deacetylated. Treatment with 1 ml. of pyridine and 0.5 m1. of acetic anhydride at 25 C. for 18 hours followed by concentration in vacuo and crystallization of the residue from acetone-ether afforded pure L-Ch10l'O11,B,17d, ZI-trihydroxy-16B-methy1-4-pregnene-3,20 di0ne 21-acetate.

Example 28.--Preparation of 2,4-dibromo 17a,21-dihydroxy-l6fi-methyl-pregnane-3,11,20-trione 21-acetate To a stirred solution of 682 mg. of 17a,21-dihydroxy- 16 8-methlpregnane- 3,11,20-trione 21-acetate (prepared as described in Example 17) in 20 ml. of chloroform and 2.25 ml. of acetic acid maintained at -20 C. was added dropwise one-half of a solution of 540 mg. of bromine in 2 ml. of chloroform and 3 ml. of acetic acid. The mixture was warmed to 0 C. and the remainder of the bromine added. Sodium acetate (0.4 g.) in 2 ml. of water was added followed by 20 mg. of sodium sulfite. The mixture was concentrated in vacuo to remove the chloroform and 20 m1. of water was added. The white powdery precipitate of 2,4-dibromo 17a,21-dihydroxy- 1613-methylpregnane-3,l 1,20-trione 21-acetate was filtered, Washed with water and dried in Yield: 920 mg. M.P. 122130 C. dec.

Example 29.-Preparation of l7a,21-dihydroxy 16f methyl-1,4'pregnadiene-3,1 1,20-trione 21-acetate AgEgP 238 m (E=15,300); xgfif 2.9-3.0, 5.75, 5.79,

5.84, 6.01, 6.16, 6.19, 112o,.; a1g +216 (G=.805)

Analysis.--Calculated for C H O C, 69.55; H, 7.30. Found: C, 69.25; H, 7.25.

Example 3 0.-Preparation of 17a,21-dihydroxy- 1 613- methyl-1,4-pregnadiene-3,1 1,20-trione This compound was obtained by treatment of 1.0 g. of 17u,21-dihydroxy IGB-methyl 1,4-pregnadiene-3,11, 20-trione 21-acetate in 30 ml. of methanol with 1 g. of potassium bicarbonate in 10 ml. of Water under nitrogen at reflux temperature for 7 minutes. The mixture was cooled, neutralized with 1 ml. of acetic acid in 10 ml. of water, the methanol removed in vacuo and the product extracted into ethyl acetate. Removal of the ethyl acetate gave crystals (900 mg.) M.P. 195-200 of the desired 17 u,21-dihydroxy-16p-methy1 1,4 pregnadiene- 3,1 1,20 trione.

Example 31.Preparation of 11 3,17o,21-trihydroxy-165- methyl-1,4-pregnadiene-3,20-dione 21-acetate To mg. of 116,l7a,21-trihydroxy-16fl-methyl-4- pregnene-3,20-dione ZI-acetate in 5 ml. of t-butanol and 0.1 ml. of acetic acid was added 50 mg. of selenium dioxide. The mixture was refluxed under nitrogen 18 hours, 50 mg. of selenium dioxide was added and the mixture refluxed an additional 24 hours. The mixture was filtered, and the filtrate taken to dryness. The residue was taken up in ethyl acetate and washed successively with aqueous sodium bicarbonate, ammonium sulfide,

dilute ammonia water, water, dilute hydrochloric acid and water and dried over magnesium sulfate. It was then treated with activated charcoal and concentrated to dryness. Crystallization of the residue from acetone-ether gave pure 11 8,17u,21-trihydrxy-I6/3-methyI-L4-pregnadiene-3,20-dione 2 l-acetate.

Example 32 Alternately, the 1,2-dehydrogenation of 11,8,l7a-2ltl'ihydroxy l6 3-methyl 4-pregnene 3,20-dione 21- acetate can be carried out microbiologically by means of bacillus sphaericus to yield 11/8,17a,2l-trihydroxy-16/S- methyl 1,4-pregnadiene 3,20-dione, which on acetylation with acetic anhydride-pyridine gives 11fi,17 x,21-trihydroxy-l6fl-methy1 1,4 pregnadiene-3,20-dione 21-acetate.

Example 33.-Preparation of 9a-fiuoro-11fi,17a,21- trihydroxy 16,8 methyl 1,4 pregnadiene 3,20- dione 21-acetate In a similar manner, 100 mg. of 9oz-fil1OI'0-11B,17a,21- trihydroxy-lGfi-methyl 4-pregnene 3,20-dione 21-acetate was treated with selenium dioxide to produce the corresponding 9u-fiuoro 11,8,17a,21-trihydroxy 16,8- methyl 1,4-pregnadiene 3,20 dione 21-acetate. Alternately, Bacillus sphaericus may be utilized. The 2l-a1cohol was prepared from the 21-acetate as in Example 26 or Example 30.

Various changes and modifications may be made in the present invention, certain preferred embodiments of which are herein disclosed, without departing from the scope thereof; to the extent that these changes and modifications are within the scope of the appended claims, they are to be considered a part of this invention.

We claim:

11. The process which comprises reacting Baal-lower References Cited UNITED STATES PATENTS 2,705,233 3/1955 Julian 260-23955 FOREIGN PATENTS 744,237 2/1956 Great Britain.

OTHER REFERENCES Julian et al: J.A.C.S. 77, 1955 pp. 46014604.

Lederer et al.: Chromatography, Elsevier Publ. Co., NY. (1953), 460 pages (p. -181 relied on).

Smith: Chromatographic Techniques (1958), 231-239 relied on.

Lederer. Chromatographic Reviews, vol. 1, 1959, pp. 135-139 relied on.

Marker et al.: J.A.C.S. 64, 1980 (1942).

Fieser et al.: Natural Products Related to Phenanthrene (1949),p. 118.

HENRY A. FRENCH, Primary Examiner U.S. Cl. X.R. 

1. THE PROCESS WHICH COMPRISES REACTING 3A-LOWER ALKANOYLOXY-16-LOWER ALKYL - 16-PREGNENE -11,20-DIONE WITH A PEROXIDIC OXIDIZING AGENT TO PRODUCE 16B-LOWER ALKYL - 16A,17A-EPOXY - 3A-HYDROXYPREGNANE - 11,20-DIONE, AND REACTING THE LATTER COMPOUND WITH HYDROGEN TO FORM 16B-LOWER ALKYL - 3A,17A-DIHYDROXY- PREGNANE-11, 20-DIONE. 